es.set.difference.v2.js 1.2 KB

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  1. 'use strict';
  2. var $ = require('../internals/export');
  3. var difference = require('../internals/set-difference');
  4. var fails = require('../internals/fails');
  5. var setMethodAcceptSetLike = require('../internals/set-method-accept-set-like');
  6. var SET_LIKE_INCORRECT_BEHAVIOR = !setMethodAcceptSetLike('difference', function (result) {
  7. return result.size === 0;
  8. });
  9. var FORCED = SET_LIKE_INCORRECT_BEHAVIOR || fails(function () {
  10. // https://bugs.webkit.org/show_bug.cgi?id=288595
  11. var setLike = {
  12. size: 1,
  13. has: function () { return true; },
  14. keys: function () {
  15. var index = 0;
  16. return {
  17. next: function () {
  18. var done = index++ > 1;
  19. if (baseSet.has(1)) baseSet.clear();
  20. return { done: done, value: 2 };
  21. }
  22. };
  23. }
  24. };
  25. // eslint-disable-next-line es/no-set -- testing
  26. var baseSet = new Set([1, 2, 3, 4]);
  27. // eslint-disable-next-line es/no-set-prototype-difference -- testing
  28. return baseSet.difference(setLike).size !== 3;
  29. });
  30. // `Set.prototype.difference` method
  31. // https://tc39.es/ecma262/#sec-set.prototype.difference
  32. $({ target: 'Set', proto: true, real: true, forced: FORCED }, {
  33. difference: difference
  34. });